Olsson warns West Brom pal Rosenberg he must fight for place
The summer signing has been restricted to just one start, in the Capital One Cup win over Yeovil.
"Markus' first task will be to get in the team, which isn't easy," Olsson told the Birmingham Mail.
"I really feel that this year we have a great depth in the squad. You look at the bench and there are a lot of really good players on there.
"That is so important, because we all know it's a long season in England.
"Everybody will get their chance at some time and, when that chance comes, you have to take it."